344 Mr. Newport on the Natural History 
the larva does not readily quit them. I left four or five specimens during the 
night, on hairs, beneath the microscope: three of the larvae were attached to 
the hairs. In the morning two of them had escaped, and one only was still 
clinging to a hair; so that we may fairly conclude that they sometimes wan- 
der in search of the object of their parasitism. 
INTERNAL ANATOMY OF STYLOPS. 
I have succeeded in tracing the alimentary canal of the larva throughout 
its whole course, and I believe am enabled somewhat to extend the observa- 
tions of Dr. Siebold on this part of its anatomy. Dr. Siebold describes the 
larvae of the species he examined, Stylops Melittæ and Xenos Rossii and sphe- 
cidarum, as having a simple czecal intestine, but no anal outlet. My own 
observations lead me to a different conclusion. The alimentary canal com- 
mences in a narrow cesophagus, which is gradually enlarged as it passes back- 
wards through the thoracic segments, until it has reached the first abdominal 
one, where it is dilated into a kind of crop. An abrupt constriction, the car- 
diac valve, separates this from the continuation of the canal, the true stomach, 
or chylific ventricle. This part is considerably enlarged, and commences 
within the posterior margin of the first abdominal segment, the fifth of the 
whole body, as in other insects. The canal then pursues nearly a direct 
course as far as the ninth segment, the fourth of the abdomen, in which it is 
folded on itself and again turns forward, that portion which passes forward 
being on the under surface. "This gives to the anterior, the uppermost portion 
of the chylific ventricle, an appearance of caecal termination. I suspect it was 
this appearance which led that distinguished observer Dr. Siebold to describe 
the canal as simple and merely cæcal. When the canal has thus passed for- 
wards for a short distance, it is again folded backwards in the next segment, 
and is then indistinctly traced onwards until seen in the thirteenth segment 
as the rectum. I have no doubt that a true anal outlet exists to the canal at 
this period of the larva state, although it is not improbable it may become 
closed at a subsequent one, when the parasite is included in the abdomen of 
the bee larva. I have indeed noticed what seems to be a demonstration that 
the canal in the young larva is not closed. While observing a larva that was 
moving along on a plate of glass, a little fecal mass seemed to be voided by 
